Author:Otto Henker

Otto Henker
Ph.D. Staff member at Zeiss in Jena. Head of the newly established "Medical Optical Instruments" and "Eyeglass" departments from 1912.[1]
This author wrote articles for the 1911 Encyclopædia Britannica.
Articles attributed to this author are designated in EB1911 by the initials "O. Hr."
Otto Henker



  1. Company History: Otto Henker

Some or all works by this author are in the public domain in the United States because they were published before January 1, 1928.

The longest-living author of these works died in 1926, so these works are in the public domain in countries and areas where the copyright term is the author's life plus 96 years or less. These works may be in the public domain in countries and areas with longer native copyright terms that apply the rule of the shorter term to foreign works.